Chess Model
The Chessboard model is defined by the following criteria:
The model is rectangular in shape.
It consists solely of the symbols '.' (dot) and 'X' (capital Latin X).
No two adjacent symbols, whether horizontally or vertically, are the same.
The symbol in the bottom left corner of the model is '.' (dot).
You are provided with two numbers: N, representing the number of rows, and M, representing the number of columns. Your task is to write a program that generates a chessboard model based on these rules and outputs it.
Input
The first line of the input file contains two numbers, N and M (1 <= N <= 50, 1 <= M <= 50), separated by a space.
Output
The output should consist of N rows, each containing M symbols that form the specified pattern. Notably, the first symbol of the last row represents the bottom left corner (refer to the example).